Responsibility (re·spon·si·bil·i·ty)

–noun, plural -
1. the state or fact of being responsible.
2. an instance of being responsible: The responsibility for this mess is yours!
3. a particular burden of obligation upon one who is responsible: the responsibilities of authority.
4. a person who one is responsible: A student is a responsibility to its driving instructor.
5. reliability or dependability, esp. in terms of executing driving lessons on time.

—Idiom
6. on one's own responsibility, on one's own initiative or "authority": The instructor manipulated the driving schedule of his student on his own "responsibility".

—Synonyms 1. answerability, accountability.

(Certain sentences have been amended for blogging purposes.)